Compatibility of Quantum Mechanics and Special Relativity

In summary, the conversation revolves around the compatibility of Quantum Mechanics and Special Relativity. The Special Theory of Relativity states that there is no variation in laws of physics for all inertial frames of reference and that the speed of light in a vacuum is the same in all inertial frames of reference. However, Quantum Mechanics appears to conflict with this theory, specifically in regards to the phenomenon of Quantum Entanglement, where entangled particles interact instantaneously with each other regardless of distance. This is referred to as "spooky action at a distance" and is seen as a breach of the second postulate of Special Relativity. However, John Bell's test in 1964 ruled out the possibility of "hidden information" being the cause of
  • #36
PeterDonis said:
No, from Bell inequality tests we know what kinds of theoretical models are not going to work. Theoretical models are not reality.
Of course. Map is not the territory. Experiments can falsify only theoretical models and not reality itself.
PeterDonis said:
Even if we talk about theoretical models, however, your apparent belief that the only viable ones given the Bell inequality tests are ones with FTL propagation is incorrect. Quantum field theory predicts violations of the Bell inequalities, and it is perfectly consistent with SR and has no FTL propagation.
Well, I meant only category of models that could attempt to model entanglement phenomena at the level of spacetime events (individual clicks in detectors). Quantum field theory is describing entanglement at the level of statistics and does not fall in that category. I should have been more specific.
 
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  • #37
zonde said:
So you are saying I can't claim that certain theoretical models won't work without providing detailed alternative model, right?
Well this isn't the place for discussing alternative models. This is a thread about compatibility between SR and QM. Your claim (or was it ?) that there are inconsistencies is based on something that does not exist: "a propagating effect". There is no such thing in QM entanglement, and there is not such FLT thing in SR.

zonde said:
That logic would require totally novel structure of spacetime. And this would go outside philosophical basis of scientific approach.
Quite the opposite, spacetime is a well defined structure that doesn't need philosophy. The logic of Bell's theorem is quite simple. Polarization filters are quite simple objects. Photons with entangled polarization are a little more unusual, that's all.
 
  • #38
Boing3000 said:
This is a thread about compatibility between SR and QM. Your claim (or was it ?) that there are inconsistencies is based on something that does not exist: "a propagating effect".
My answer about compatibility of SR and QM was that they are compatible. That is my answer to the title of this thread.
But opening post has more context for this question with references to Bell inequalities. So my claim as related to this more broader context of the question is that there indeed is incompatibility. And that incompatibility is between popular interpretation of SR (not SR itself) and experimental results of loophole free Bell inequality tests (not QM's statistical description of entanglement). In particular my claim is that these experimental results can not be modeled with scientific spacetime events based model where any physical effect propagates no faster than speed of light in vacuum.
Boing3000 said:
Quite the opposite, spacetime is a well defined structure that doesn't need philosophy. The logic of Bell's theorem is quite simple. Polarization filters are quite simple objects. Photons with entangled polarization are a little more unusual, that's all.
Maybe I misunderstood what you said. This is your statement: "if something (like a polarization property value) is at two places at the "same instant" it is the same thing"
Did you mean it's the same physical thing or more like it's two physical things that share the same description (in the sense of some kind of information)?
 
  • #39
zonde said:
In particular my claim is that these experimental results can not be modeled with scientific spacetime events based model where any physical effect propagates no faster than speed of light in vacuum.
But that claim is false. Non-locality is a perfectly valid non-stochastic model for explaining the correlation, because there is no "propagating effect"

zonde said:
Did you mean it's the same physical thing or more like it's two physical things that share the same description (in the sense of some kind of information)?
Both. There are two local physical photons sharing one non-local physical property "polarization angle". I consider everything that can be measured as physical.
 
  • #40
Boing3000 said:
Non-locality is a perfectly valid non-stochastic model for explaining the correlation, because there is no "propagating effect"
I don't see non-locality (as I understand it from your posts) as perfectly valid model. For me it seems more like Matrix movie (solipsistic worldview) inspired hand waving. Sorry. Maybe I'm missing something.
 
  • #41
zonde said:
I don't see non-locality (as I understand it from your posts) as perfectly valid model.
OK, but the fact you don't see it, does not make it an invalid model. Logic make it valid (like Bell's proof). Logic is quite the opposite of solipsistic.

In my book, what makes a model "hand wavy" it the use of undefined/uncalled for "action at a distance" or "propagating effect".
 
  • #42
Boing3000 said:
Logic make it valid
Logic gives rules for arguing. It does not make particular conclusion valid. Arguments do that.
 
  • #43
zonde said:
Logic gives rules for arguing. It does not make particular conclusion valid. Arguments do that.
And the many logical argumentation of Bell (an others) have done that.

So unless you can argue otherwise, with some logically described phenomenon (like "a propagating effect") or by faulting Bell's proof (which I doubt greatly), there is no point in continuing that conversation.
 
  • #44
Boing3000 said:
there is no point in continuing that conversation.
Sure
 

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